Field of the Invention
This invention relates generally to Buck, Boost, and other types of switching converters, obtaining high DC-gain in the switching converters.
Description of Related Art
DC-DC converters are important in portable electronic devices such as cellular phones and laptop computers, which are supplied with power from primarily batteries. Such electronic devices often contain several sub-circuits, each with its own voltage level requirement different from that supplied by the battery or an external supply. Additionally, the battery voltage declines as its stored energy is drained. Switched DC-DC converters offer a method to increase voltage from a partially lowered battery voltage, thereby saving space instead of using multiple batteries to accomplish the same goal.
Electronic switch-mode DC-DC converters convert one DC voltage level to another, by storing the input energy temporarily and then releasing that energy to the output at a different voltage. The storage may be in a magnetic field storage component such as an inductor. This conversion method is more power efficient and beneficial to increasing the running time of battery-operated devices.
Most DC-DC converters regulate the output voltage and use an integrator in the control loop for achieving high DC-gain in the switching converter. Drawbacks of these types of switching converters include complexity, electronic noise and to some extent cost, although this has come down with advances in chip design. Conventional designs require large capacitors and allow only high gain in pulse-width modulation mode. Many Bucks, Boosts, and other types of switching converters operate in multiple modes, and a traditional scheme would not account for this.